Differential amplifiers and operational amplifiers are often used in feedback circuits such that under normal operation the amplifier is in a substantially steady state with small differences in voltage between the two inputs.
However, when the inputs are far apart, the amplifier can enter a non-linear mode to rapidly change the output current of the amplifier. The slew rate associated with these changes can cause problems for feedback loops and the feedback loop may enter an unstable state. As a result, improvements to the slew rate of an amplifier can improve the stability characteristics, as well as other characteristic of feedback loops including these amplifiers. Such other characteristics may include clipping and other distortions.
There is a need to enhance the slew rate of an amplifier without affecting other small signal and steady-state characteristics of the amplifier.